There are two reasons the field line flux through a closed surface may be zero: because the field is zero everywhere or because the outward flux is balanced by an equal inward flux. Why can't the latter situation be true for the Gaussian surface in Figure 24.12c?

Transcribed Image Text:

Figure 24.12 Using spherical Gaussian surfaces to examine the electric fields of a charged particle and a uniformly charged spherical shell. The electric fields, Gaussian surfaces, and charged shell are spherical and are shown here in cross section. charged particle (a) E hollow shell with same charge as particle (b) E E spherical Gaussian surface Gaussian surface outside shell: electric field is same as for particle. Gaussian surface inside shell: encloses no charge, so electric field must be zero.